Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7030, USA.
J Acquir Immune Defic Syndr. 2012 Dec 1;61(4):515-21. doi: 10.1097/QAI.0b013e31827076a4.
HIV infections increased 48% among young Black men who have sex with men (MSM) in the United States between 2006 and 2009. Incomplete understanding of this trend undermines prevention strategy development. We investigated a sexual network to characterize the risk environment in which young Black MSM acquire HIV.
Persons reported to the state after diagnosis of HIV or syphilis were included, along with sexual partners. We used network mapping alongside descriptive and bivariate statistics to characterize network connections. Generalized linear models assessed predictors of having untraceable sex partners.
The network included 398 individuals and 419 sexual relationships. Three-quarters were Black (n = 299); 92% were MSM. Median age at first network appearance was 26 years and decreased over time (P < 0.001). HIV prevalence was at least 29% (n = 117); serostatus was unknown for 47% of the network, either because they were untraceable (n = 150) or refused HIV testing (n = 39). One in 5 network members diagnosed with HIV had a subsequent incident sexually transmitted infection. In multivariable models, one-time encounters increased the risk of having an untraceable partner (risk ratio = 4.51, 95% CI: 2.27 to 8.97), whereas being acutely HIV infected at diagnosis reduced it (risk ratio = 0.27, 95% CI: 0.08 to 0.89).
HIV prevalence in this sexual network of young Black MSM rivals that of sub-Saharan Africa, reflecting dramatically increased risk of acquiring HIV from the moment one entered the network. Prevention efforts for this population must consider the effect of sexual networks on HIV risk and find ways of leveraging network structure to reduce transmission.
2006 年至 2009 年间，美国与男性发生性行为的青年黑人男性（MSM）中的 HIV 感染率上升了 48%。对这一趋势缺乏充分了解，会阻碍预防策略的制定。我们研究了一个性网络，以描述青年黑人 MSM 感染 HIV 的风险环境。
本研究纳入了在诊断出 HIV 或梅毒后向州政府报告的患者及其性伴侣。我们使用网络绘图以及描述性和双变量统计分析来描述网络联系。广义线性模型评估了有无踪迹可寻的性伴侣的预测因素。
该网络包括 398 名个体和 419 段性关系。四分之三为黑人（n=299）；92%为 MSM。首次出现在网络中的中位年龄为 26 岁，且随时间推移而降低（P<0.001）。HIV 感染率至少为 29%（n=117）；网络中 47%的人的血清学状态未知，要么是因为无法追踪（n=150），要么是因为拒绝 HIV 检测（n=39）。在诊断出 HIV 的网络成员中，每 5 人就有 1 人随后发生了性传播感染。在多变量模型中，一次性接触增加了有无踪迹可寻的伴侣的风险（风险比=4.51，95%CI：2.27 至 8.97），而诊断时急性 HIV 感染则降低了这种风险（风险比=0.27，95%CI：0.08 至 0.89）。
该青年黑人 MSM 性网络中的 HIV 感染率与撒哈拉以南非洲相媲美，这反映出他们从进入网络的那一刻起，感染 HIV 的风险大大增加。必须考虑性网络对 HIV 风险的影响，并寻找利用网络结构减少传播的方法，以制定针对该人群的预防措施。
